I. Field
The present disclosure relates generally to communication, and more specifically to techniques for sending control information in a wireless communication network.
II. Background
Wireless communication networks are widely deployed to provide various communication content such as voice, video, packet data, messaging, broadcast, etc. These wireless networks may be multiple-access networks capable of supporting multiple users by sharing the available network resources. Examples of such multiple-access networks include Code Division Multiple Access (CDMA) networks, Time Division Multiple Access (TDMA) networks, Frequency Division Multiple Access (FDMA) networks, Orthogonal FDMA (OFDMA) networks, and Single-Carrier FDMA (SC-FDMA) networks.
A wireless communication network may include a number of base stations that can support communication for a number of user equipments (UEs). A UE may communicate with a base station via the downlink and uplink. The downlink (or forward link) refers to the communication link from the base station to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the base station.
A wireless communication network may support operation on multiple carriers. A carrier may refer to a range of frequencies used for communication and may be associated with certain characteristics. Such characteristics, for example, may be conveyed in system information that describes operation on the carrier. A carrier may also be referred to as a component carrier (CC), a frequency channel, a cell, etc. A base station may send data transmissions on multiple carriers for the downlink (or downlink carriers) to a UE. The UE may send control information on a carrier for the uplink (or uplink carrier) to support data transmissions on the multiple downlink carriers.